The present invention relates to an improvement of a connector housing coupling mechanism for coupling a pair of male and female connector housings with each other which are used for connection of electric wires.
Recently, in accordance with an increase in the number of signal lines due to increased electronic parts, many kinds of male and female connector housings which are used for connection of electric wires are designed so as to accommodate a large number of terminal pieces or to be adopted for a multiterminal connector. In a pair of such male and female connector housings, there are tendencies to set the contact pressure exerted between terminal pieces to be higher than a specified value irrespective of the number of terminals in view of influence of vibration or the like. When such male and female connector housings are to be mated or unmated, a mating or unmating force larger than the friction engaging force appearing between the terminal pieces must be exerted. In the case where terminal pieces to be connected are increased in number, consequently, it is required to exert a very large force in order to couple male and female connector housings with each other or separate them from each other.
To comply with this, conventionally, various connector housing coupling mechanisms which are designed so as to facilitate the coupling and separation of male and female connector housings have been proposed. For example, Japanese Utility Model Unexamined Publication (Kokai) No. SHO 52-133993 discloses a connector housing coupling mechanism in which an engaging projection is formed on a side face of one of male and female connector housings, and an operating lever is rotatably supported on a side face of the other one of the connector housings. When the operating lever is rotated under the state where the engaging projection is received in a cam groove formed in the operating lever, the male and female connector housings are coupled with or separated from each other.
In the connector housing coupling mechanism, as shown in FIGS. 8(a) and 8(b), an engaging projection 3 is formed on a side face of a female connector housing 1 which is the side face of one of the male and female connector housings, and an operating lever 4 is disposed on a side face of a male connector housing 2 which is the side face of the other connector housing, in such a manner that the operating lever 4 is rotatable in a plane which is substantially parallel to the directions of mating and unmating the connector housings. The operating lever 4 is provided with a guide groove 5 which receives and guides the engaging projection 3 depending on the rotating position of the operating lever. The guide groove 5 is so configured that the innermost portion is closer to the rotation center of the operating lever 4 than the entrance of the groove. In this configuration, when the operating lever 4 is rotated while the engaging projection 3 is received in the guide groove 5, the male and female connector housings 2 and 1 can be coupled with or separated from each other with a small operating force.
The male connector housing 2 on which the operating lever 4 is rotatably supported is provided with a locking spring 6 functioning as lever locking means. The locking spring 6 engages with the operating lever 4 which is rotated so as to accomplish a state where the male and female connector housings 2 and 1 are completely coupled with each other. As shown in FIG. 8(b), the operating lever 4 is locked so as not to be accidentally rotated in the direction along which the male and female connector housings 2 and 1 are separated from each other.
In such a connector housing coupling mechanism of the operating lever type, even when the male connector housing 2 which is provided with the operating lever 4 stands alone as shown in FIG. 9, the operating lever 4 may be rotated to engage with the locking spring 6 to enter the lock-up state where the operating lever 4 is locked so as not to be rotated.
When the male connector housing 2 in which the operating lever 4 has once been engaged with the locking spring 6 is to be coupled with the female connector housing 1, the operating lever 4 must be disengaged from the locking spring 6 before conducting the coupling operation so that the lock-up state is canceled, thereby producing a problem in that the workability of the connector coupling operation is impaired.